GB697714A - Improvements in or relating to sediment handling or agitating devices - Google Patents

Abstract

697,714. Gravity-separation apparatus. HARDINGE, H. Feb. 13, 1952 [Feb. 17, 1951], No. 3808/52. Class 46 A settling-tank of the kind having scrapers rotating about a vertical axis and conventional in general design i s characterized chiefly by the provision of a combination thrust - and - radial bearing assembly disposed between an annular supporting member and an annular portion of a gear-wheel driving the scraper shaft to prevent tilting of the shaft. A hollow torque shaft 30, Fig. 3, is driven indirectly by a worm-gear-wheel 56 in a casing 46 supported on cross-beams 44. The casing 46 has an upstanding annular portion 52 having a seat 54, Fig. 8, to which is clamped by members 76 and bolts 78 the inner race 66 of a thrust-and-radial bearing assembly 64. The outer race 66a of the bearing assembly is similarly clamped to a seat 58 in the underside of the wheel 56 where the wheel is shaped to form an offset flange 60. Rotation of the wheel 56 is transmitted through a drive tube 90 secured to the flange 60 and having cam slots 98, Fig. 5, engaging rollers 102 on a shaft 100 extending through the upper end of the torque shaft 30. When rotation of the shaft 30 is impeded by engagement of the scrapers with an obstruction in the tank the drive tube 90 continues to be rotated by the wheel 56 and as a result the rollers 102 ride up the cam slots 98, the scrapers in turn being lifted over the obstruction. Excessive rise of the shaft 30 brings about engagement of an extension 104 on the shaft 30 with. a switch 114 to cut off the current to an electric motor driving a worm 80 which engages with the wheel 56. The switch 114 may also sound an alarm. The extension 104 slides in a bearing sleeve 108 in a cover secured to the drive tube 90 and threads into the boss of a hand-wheel 116 by which the scrapers may be raised or lowered and their height adjusted. Peripheral openings (not shown) are provided in the flange 60 to permit access to the bolts 78 when the drive tube 90 is removed. Tilting of the torque tube 30 is substantially prevented by the bearing described and additionally by the bearing sleeve 108, a construction 96 in the drive tube 90 and a lower guide bearing 118, Fig: 3. The bottom and side walls of the casing 46 form an oil-bath 50 for the worm and wheel. A yieldable seal 122 prevents ingress of liquid, solid or vapour into the casing 46 and wipes the tube 30 when it is raised. In the modification of Fig. 8 the mechanism for raising the tube 30 is dispensed with; the flange 60 is extended inwards to 124 and is connected by bolts 126 with a sleeve 128 which extends downwards a short way below the casing 46, its lower end being connected to the upper end of the tube 30. Apertures 130 provide access to the bolts 78.